Lines Infinite 

Lines Infinite, released in 2017 on Steam (Linux, Windows and mac), is a puzzle game available at a ridiculously low price (€0.99, and often discounted at €0.29 according to steamdb).

It comes with a hundred numberlink puzzles, which are logic puzzles involving connecting numbers on a grid (see Wikipedia), and a quickly-annoying music and sound effects, which I ended up muting after 20 minutes of play time.

The UI is good, because there’s no useless stuff: you boot the game, and you can immediately start playing it - there’s no main menu, no “save” to load. You pick the level you want to play, and there you go. But that’s about it, as you’ll quickly be frustrated by the inability to “redraw” or “continue” a line without having to erase it.

Moreover, this game is plagued by its (non-existent) difficulty curve: early-game levels felt somehow harder than mid-game ones, whereas you sometimes encounter extremely easy levels seemingly out of nowhere. Balancing the difficulty in puzzle games is known to be a tricky matter, but said absence of a difficulty curve annihilates all sense of progress you might get, aside from the Steam achievements.

Finally, a tutorial could help onboard players that do not know how numberlink puzzles work. I don’t say it’s necessary, but it might have helped improve my opinion about this game.

To put things in a nutshell: Lines Infinite remains a decent puzzle game, thanks to its price and the average 3 hours of playtime you can expect from it (according to HowLongToBeat).